Welcome to Week 10 for the 2025 growing season! This week includes: • Weather synopsis • Predicted wheat midge development • Predicted grasshopper development • Predicted diamondback moth development • Bertha armyworm • Wheat stem sawfly • Mealybug • Aphids in field crops • Lygus bug monitoring • Cabbage seedpod weevil • Provincial insect pest report links • Crop report links • Previous posts
Catch Monday’s Insect of the Weekfor Week 10 – This year features lesser-known insect pest species to help producers remain vigilant! Learn more about the Pollen beetle!
Questions or problems accessing the contents of this Weekly Update? Please contact us so we can connect you to our information. Past “Weekly Updates” can be accessed on our Weekly Update page.
Dylan Sjolie, Tamara Rounce, Meghan Vankosky and Jennifer Otani
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Week 10
The seven-day average temperature across the Canadian prairies was approximately 17 °C from June 30 to July 06, 2025 (Fig. 1). These temperatures are slightly above the long-term climate normal (Fig. 3). Grande Prairie and the surrounding area continue to be cooler over the last seven days. In contrast, most of Saskatchewan and Manitoba experienced temperatures above 17 °C (Fig. 1) and these areas were some of the coolest and warmest points over the last 30 days (Fig. 2). As the growing season progresses, average temperatures across the Prairies continue to be slightly higher than the long-term climate normal (Fig. 3).
Figure 1. Seven-day average temperature (°C) observed across the Canadian prairies for June 30-July 6, 2025.Figure 2. Thirty-day average temperature (°C) observed across the Canadian prairies for the period of June 7-July 6, 2025.Figure 3. Growing season average temperature (°C) observed across the Canadian prairies for the period of April 1-July 6, 2025.
Most of western Canada received less than 20 mm of cumulative rainfall over the past seven days (Fig. 4; for the period of June 30 – July 6, 2025). In June, areas surrounding Edmonton, Calgary, Lethbridge, and Saskatoon received over 100 mm of rainfall, whereas much of Manitoba and the Peace River region received less than 70 mm (Fig. 5). So far, the cumulative rianfall across the Canadian prairies for the growing season is slightly below normal (Fig. 6).
Figure 4. Seven-day average precipitation (mm) observed across the Canadian prairies for the period of June 30-July 6, 2025.Figure 5. Thirty-day cumulative rainfall (mm) observed across the Canadian prairies for the period of June 7-Jul 6, 2025.Figure 6. Growing season cumulative rainfall (mm) observed across the Canadian prairies for the period of April 1-July 6, 2025.
Dylan Sjolie, Tamara Rounce, Meghan Vankosky and Jennifer Otani
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Week 10
The emergence of wheat midge (Sitodiplosis mosellana) needs to be synchronized with the development of wheat heads for successful larval development. One factor that determines the timing of adult wheat midge emergence is spring precipitation. Cumulative rainfall between 25-30 mm in May and June is required for overwintered larval cocoons to complete larval and pupal development in the spring. When cumulative rainfall is below 25-30 mm in May and June, the completion of larval development may be delayed or postponed to future growing seasons, resulting in delayed or erratic adult wheat midge emergence in late June and July.
The model used to predict wheat midge development during the growing season was developed and is described in a published scientific paper: Olfert, O., R.M. Weiss, M. Vankosky, S. Hartley, J.F. Doane. 2020. Modelling the tri-trophic population dynamics of a host crop (Triticum aestivum; Poaceae), a major pest insect (Sitodiplosis mosellana; Diptera: Cecidomyiidae), and a parasitoid of the pest species (Macroglenes penetrans; Hymenoptera: Pteromalidae): a cohort-based approach incorporating the effects of weather. The Canadian Entomologist 152: 311-329. DOI: 10.4039/tce.2020.17
As of July 6, 2025, the model indicates that, where wheat midge populations are present, populations are at various life stages based on when they received the necessary rainfall to complete larval development (Fig. 1). Populations along the AB/SK border that did not get rainfall until middle of June are still in the larval phase (Fig. 2). Other areas (eastern AB) that received the necessary rain in early June consist of midge populations in the pupal stage (Fig. 2). Model output suggests that adults have emerged in areas along the southeast border between SK/MB and are now laying eggs (Fig. 3).
Figure 1. Percent of wheat midge larval population (Sitodiplosis mosellana) predicted to be in the larval stage across western Canada, as of July 6, 2025.Figure 2. Percent of wheat midge larval population (Sitodiplosis mosellana) predicted to be in the pupal stage across western Canada, as of July 6, 2025.Figure 3. Percent of wheat midge larval population (Sitodiplosis mosellana) predicted to be in the egg stage across western Canada, as of July 6, 2025.
Please refer to the historical wheat midge survey maps and particularly the 2024 results. Historical survey information paired with updated predictive model outputs help identify areas at risk of wheat midge damage in 2025.
In-Field Monitoring:When scouting wheat fields, pay attention to the synchrony between flying midge and anthesis. In-field monitoring for wheat midge should be carried out in the evening (preferably after 8:30 pm or later) when the female midges are most active. On warm (at least 15 ºC), calm evenings, the midge can be observed in the field, laying their eggs on the wheat heads (Fig. 3). Midge populations can be estimated by counting the number of adults present on 4 or 5 wheat heads. Inspect the field daily in at least 3 or 4 locations during the evening.
Figure 3. Wheat midge (Sitodiplosis mosellana) laying their eggs on a wheat head. Photo: AAFC-Beav-S. Dufton and A. Jorgensen.Figure 4. Macroglenes penetrans, a parasitoid wasp that attacks wheat midge, measures only ~2 mm long. Photo: AAFC-Beav-S. Dufton.
REMEMBER that in-field counts of wheat midge per head remain the basis of the economic threshold decision. Also remember that the parasitoid, Macroglenes penetrans (Fig. 4), is actively searching for wheat midge at the same time. Preserve this parasitoid whenever possible and remember insecticide control options for wheat midge also kill these beneficial insects who help reduce midge populations.
Economic Thresholds for Wheat Midge: a) To maintain optimum No. 1 grade: 1 adult midge per 8 to 10 wheat heads during the susceptible stage. b) To maintain yield only: 1 adult midge per 4 to 5 heads. At this level of infestation, wheat yields will be reduced by approximately 15% if the midge is not controlled. Inspect the developing kernels for the presence of larvae and larval damage.
Wheat midge was featured as the Insect of the Week in 2023 (for Wk08). Be sure to also review wheat midge and its doppelganger, the lauxanid fly, featured as the Insect of the Week in 2019 (for Wk11) – find descriptions and photos to help with in-field scouting! Additionally, the differences between midges and parasitoid wasps were featured as the Insect of the Week in 2019 (for Wk12). Remember – not all flying insects are mosquitoes nor are they pests! Many are important parasitoid wasps that regulate insect pest species in our field crops OR pollinators that perform valuable ecosystem services!
Additional information can be accessed by reviewing the Wheat midge pages extracted from the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Field Guide” (2018) accessible as a free downloadable PDF in either English or French on our new Field Guides page.
Dylan Sjolie, Tamara Rounce, Meghan Vankosky and Jennifer Otani
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Week 10
The grasshopper model was developed for the migratory grasshopper, but closely represents the development of the other primary pest grasshopper species found in the prairie region. The model uses weather from the current growing season to estimate the current status of grasshopper populations, but keep in mind that grasshoppers might not be present in all parts of the prairie region. Field scouting is imperative; the model estimates can be used to help time scouting activities.
The phenology model for grasshopper development on the Canadian prairies is based on: Olfert, O., R.M. Weiss, D. Giffen, M.A. Vankosky. 2021. Modelling ecological dynamics of a major agricultural pest insect (Melanoplus sanguinipes; Orthoptera: Acrididae): a cohort-based approach incorporating the effects of weather on grasshopper development and abundance. Journal of Economic Entomology 114: 122-130. DOI: 10.1093/jee/toaa254
Model simulations were used to estimate development of grasshoppers as of July 6, 2025. The model outputs predict grasshopper populations, where present, are primarily comprised of fourth instar individuals (Fig. 1). The model outputs correspond with field observations made July 4, 2025, from sentinel sites between Saskatoon and Rosetown, Saskatchewan. Based on the model estimates, grasshopper populations in southern Manitoba, east of Lethbridge, and surrounding Swift Current are predicted to be comprised of higher numbers of fifth instar individuals (Fig. 2). Adults are expected to begin appearing in these regions within the next few weeks.
Figure 1. Predicted grasshopper (Melanoplus sanguinipes) development, presented as average instar, across the Canadian Prairies as of July 6, 2025.Figure 2. Predicted grasshopper (Melanoplus sanguinipes) development, presented as the percent of the population reaching 5th instar stage, across the Canadian prairies, as of July 6, 2025.
Grasshopper Scouting Tips: ● Review grasshopper diversity and photos of nymphs, adults, and non-grasshopper species (Gavloski, Williams, Underwood, Johnson, Otani) to aid with field scouting from egg hatch and onwards. The PDF includes photos to help differentiate native versus pest grasshopper species plus froghopper, treehopper or even katydid species. ● It is best to scout on warm days when grasshopper nymphs are more active and easier to observe. ● Carefully check roadside ditches and along field edges but also check the edge of the crop and into the actual field. ● Younger or earlier instar nymphs are easier to manage – visit sites every few days to stay on top of local field conditions. ● A sweep-net can ‘detect’ grasshopper nymphs, however, economic thresholds for grasshoppers are based on the number of grasshoppers per square-metre counts. ● Access the PPMN’s Grasshopper Monitoring Protocol as a guide to help implement in-field monitoring. ● Review grasshopper lifecycle, damage and scouting and economic thresholds to support sound management decisions enabling the preservation of beneficial arthropods and mitigation of economic losses.
Important – A preliminary summary of available thresholds for grasshoppers has been kindly shared by Dr. J. Tansey (Saskatchewan Agriculture) in Table 1. When scouting, compare in-field counts to the available threshold value for the appropriate host crop AND for field or ditch situations. Available thresholds (nominal and economic) help support producers while protecting beneficials (i.e., predators, parasitoids, and pathogens) that regulate natural populations of grasshoppers.
Dylan Sjolie, Tamara Rounce, Meghan Vankosky and Jennifer Otani
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Week 10
Diamondback moths (DBM; Plutella xylostella) are a migratory invasive species. Each spring, adult populations migrate northward to the Canadian prairies on wind currents from infested regions in the southern or western U.S.A. Upon arrival to the prairies, migrant diamondback moths begin to reproduce and this results in subsequent non-migrant populations that may have three or four generations during the growing season.
Spring Pheromone Trap Monitoring of Adult Males: Across the Canadian prairies, spring monitoring is initiated to acquire weekly counts of adult moths (Fig. 1) attracted to pheromone-baited delta traps deployed in fields. Weekly trap interceptions are observed to generate cumulative counts. These cumulative count estimates are broadly categorized to help producers prioritize and time in-field scouting for larvae.
Figure 1. Adult diamondback moth.
Diamondback moths were captured on pheromone traps across western Canada from mid- to late-May in 2025. Once adults arrive, there can be several in-season, non-migrant generations of diamondback moth developing throughout the remainder of the growing season. Warm, dry weather tends to promote rapid development of high-density populations of larvae capable of causing severe damage to host crops, including canola.
The model for diamondback moth development on the prairies was developed by Ross Weiss and Owen Olfert. Model simulations were used to estimate the number of non-migrant generations of diamondback moth (Plutella xylostella).
As of July 6, 2025, model outputs suggest that diamondback moth populations have moved into the second non-migrant generation across much of the Canadian prairies except for areas in eastern Alberta and the Peace River region (Fig. 2).
Figure 2. Predicted number of in-season generations of diamondback moth (Plutella xylostella) expected to have developed across the Canadian prairies, as of July 6, 2025.
Please refer to this week’s Provincial Insect Pest Report Links to find the most up-to-date information summarizing weekly cumulative counts compiled by provincial pheromone trapping networks across the Canadian prairies in 2025.
In-Field Monitoring:Remove plants in an area measuring 0.1 m² (about 12″ square), beat them onto a clean surface and count the number of larvae (Fig. 3) dislodged from the plant. Repeat this procedure at least in five locations in the field to get an accurate count.
Figure 3. Diamondback larva measuring ~8mm long. Note brown head capsule and forked appearance of prolegs on posterior.
The economic threshold for diamondback moth in canola at the advanced pod stage is 20 to 30 larvae/ 0.1 m² (approximately 2-3 larvae per plant). Economic thresholds for canola or mustard in the early flowering stage are not available. However, insecticide applications are likely required at larval densities of 10 to 15 larvae/ 0.1 m² (approximately 1-2 larvae per plant).
Figure 4. Diamondback moth pupa within silken cocoon.
The phenology model for bertha armyworm development on the Canadian prairies was developed by Ross Weiss and Owen Olfert. Model simulations used to estimate development of bertha armyworm are now complete for the 2025 growing season. Now, in-field scouting for larvae is important!
Figure 1 includes photos of the various life stages of the bertha armyworm. There is one generation per year and pupae overwinter in the soil (Fig. 1, C). Each growing season, green unitraps utilizing pheromone lures are deployed and checked weekly over a 6-week window. Cumulative counts generated from the pheromone traps are used to estimate subsequent bertha armyworm densities. The cumulative moth count data is compiled using geospatial maps then posted to support and time in-field scouting for damaging populations of larvae by mid-July through to August.
Figure 1. Stages of bertha armyworm from egg (A), larva (B), pupa (C), to adult (D). Photos: J. Williams (Agriculture and Agri-Food Canada).
Please refer to this week’s Provincial Insect Pest Report Links to find the most up-to-date information summarizing weekly cumulative counts compiled by provincial pheromone trapping networks across the Canadian prairies in 2025. For example, Manitoba Agriculture’s June 19th Crop Pest Report includes Figure 2 with a reminder that other moth species are actively flying now so examine wing colourations and patterning carefully when checking the contents of bertha armyworm pheromone traps! Clover cutworm can be common by-catch in pheromone traps designed to monitor bertha armyworm, but also those designed to monitor true armyworm.
Figure 2. Comparison of diagnostic wing features of three moth species. Images and information all courtesy of Manitoba Agriculture, J. Gavloski who originally included in the June 19, 2025, issue of the Manitoba Crop Pest Update.
Biological and monitoring information related to bertha armyworm in field crops is posted by the provinces of Manitoba, Saskatchewan, Alberta and the Prairie Pest Monitoring Network. Also, refer to the bertha armyworm pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (2018), accessible as a free downloadable PDF in either English or French on our Field Guides page. Also consider reviewing this 2019 Insect of the Week featuring bertha armyworm and its doppelganger, the clover cutworm!
Native to North America, the wheat stem sawfly is an economic pest depending on spring and durum wheat as its main crop hosts. These insects also target winter wheat, rye, grain corn and barley, in addition to feeding on native grass species. It is interesting to note that wheat stem sawflies do not feed on oat crops, as oats are toxic to wheat stem sawfly.
An adult wheat stem sawfly. Picture by Dylan Sjolie, AAFC-Saskatoon.
Wheat stem sawfly larvae feed on pith inside the stems of their host plant. Their feeding activity affects crop yield and quality. As infested host plants mature, the larvae travel down the stem to its base, where “V” shaped notches are cut into the stem a little above ground level. These notches leave plants vulnerable to collapsing or lodging, especially during wind events. Because wheat stem sawflies also breed and develop on native grass species, economic damage tends to be most prevalent around crop margins where native and agricultural plants are found close together.
An adult wheat stem sawfly. Picture by Dylan Sjolie, AAFC-Saskatoon.
Adult wheat stem sawflies are 8–13 mm long with a wasp-like resemblance, due to their black body and yellow legs. Females have an egg-laying organ (an ovipositor) that extends from their abdomen. When resting on plant stems, these insects will point their heads downward. Mature larvae are 13 mm long and resemble whitish worms with brown heads.
Biological and monitoring information related to wheat stem sawflies in field crops can be found on our Monitoring Protocols page as well as on provincial Agriculture Ministry pages (Manitoba, Saskatchewan and Alberta).
Mealybugs can be found in field crops growing in western Canada. The Haanchen barley mealybug (Hemiptera: Pseudococcidae) Trionymus haancheni McKenzie, feeds on barley. In contrast, the Utah grass mealybug (T. utahensis) has been observed to feed on various grasses in the USA, and it was reported in British Columbia feeding on Elymus piperi Bowden and Agropyron sp, both plant hosts in the family Gramineae (Alvarez 2004).
In some ways, mealybugs are similar to aphids; they are sucking insects, can generate multiple generations per year, and they reproduce both sexually and asexually. Mealybugs secrete a white, wax-like substance that can initially appear as a white cottony layer on the lower stems and crown of the host plant. Additionally, mealybugs secrete a sticky residue that serves as an excellent medium for diseases to develop on (e.g., black moldy spots that can form on top of the white, cottony secretions).
Figure 1. A mealybug on barley (cv. Esma) observed in field growing near Woking AB on July 4, 2025; three images feature a total of 4 mealybugs. Photos kindly shared by: B. Skarberg, Proven Ag Solutions Ltd.
Infestations are sporadic but this species tends to prosper in warmer, drier field conditions. There is no nominal or economic threshold for this species. Beneficial insects like general predators and parasitoid wasps will consume or attack mealybugs so preserve these species in fields whenever possible. In this case, the highly concealed nymphs and ovisacs are extremely difficult to manage using contact insecticides.
Biological and monitoring information for this insect pest species is accessible as a mealybug page within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (2018). The entire guide is accessible as a free downloadable PDF in either English or French on our Field Guides page.
Additionally, several aphid pest species are described in the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (2018) which is accessible as a free downloadable PDF in either English or French on our Field Guides page. PDF copies of the individual pages have been linked below to access quickly: • Corn leaf aphid or Rhopalosiphum maidis (Fitch) • English grain aphid or Sitobion (Macrosiphum) avenae (Fabricius) • Oat-birdcherry aphid or Rhopalosiphum padi (Linnaeus) • Pea aphid or Acyrthosiphon pisum (Harris) • Potato aphid or Macrosiphum euphorbiae (Thomas) • Soybean aphid or Aphis glycines (Matsumura) • Turnip aphid or Lipaphis erysimi (Kaltenbach) • Sugar beet root aphid or Pemphigus betae Doane • Russian wheat aphid or Diuraphis noxia (Mordvilko)
Lygus bugs are polyphagous (i.e., feed on plants belonging to several Families of plants) and multivoltine (i.e., capable of producing multiple generations per year). Both the adult (Fig. 1) and five nymphal instar stages (Fig. 2) are a sucking insect that focuses feeding activities on developing buds, pods and seeds. Adults overwinter in northern climates. The economic threshold for Lygus in canola is applied at late flower and early pod stages.
Recent research in Alberta has resulted in a revision to the thresholds recommended for the management of Lygus in canola. Under ideal growing conditions (i.e., ample moisture) a threshold of 20-30 lygus per 10 sweeps is recommended. Under dry conditions, a lower threshold may be used, however, because drought limits yield potential in canola, growers should be cautious if considering the use of foliar-applied insecticide at lygus densities below the established threshold of 20-30 per 10 sweeps.In drought-affected fields that still support near-average yield potential, a lower threshold of ~20 lygus per 10 sweeps may be appropriate for stressed canola. Even if the current value of canola remains high (e.g., >$19.00 per bu), control at densities of <10 lygus per 10 sweeps is not likely to be economical. Research indicates that lygus numbers below 10 per 10 sweeps (one per sweep) can on occasion increase yield in good growing conditions – likely through plant compensation for a small amount of feeding stress.
Figure 1. Adult Lygus lineolaris (5-6 mm long) (photo: AAFC-Saskatoon).
Figure 2. Fifth instar lygus bug nymph (3-4 mm long) (photo: AAFC-Saskatoon).
Damage: Lygus bugs have piercing-sucking mouthparts and physically damage the plant by puncturing the tissue and sucking plant juices. The plants also react to the toxic saliva that the insects inject when they feed. Lygus bug infestations can cause alfalfa to have short stem internodes, excessive branching, and small, distorted leaves. In canola, lygus bugs feed on buds and blossoms and cause them to drop. They also puncture seed pods and feed on the developing seeds causing them to turn brown and shrivel.
Scouting tips to keep in mind: Begin monitoring canola when it bolts and continues until seeds within the pods are firm. Since adults can move into canola from alfalfa, check lygus bug numbers in canola when nearby alfalfa crops are cut.
Sample the crop for lygus bugs on a sunny day when the temperature is above 20 °C and the crop canopy is dry. With a standard insect net (38 cm diameter), take ten 180 ° sweeps. Count the number of lygus bugs in the net. Sampling becomes more representative IF repeated at multiple spots within a field so sweep in at least 10 locations within a field to estimate the density of lygus bugs.
Biological and monitoring information related to Lygus in field crops is posted by the provinces of Manitoba or Alberta fact sheets or the Prairie Pest Monitoring Network’s monitoring protocol. Also refer to the Lygus pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (2018) accessible as a free downloadable PDF in either English or French on our new Field Guides page. The Canola Council of Canada’s “Canola Encyclopedia” also summarizes Lygus bugs. The Flax Council of Canada includes Lygus bugs in their Insect Pest downloadable PDF chapter plus the Saskatchewan Pulse Growers summarize Lygus bugs in faba beans.
There is one generation of cabbage seedpod weevil (CSPW; Ceutorhynchus obstrictus) per year. The overwintered adult is an ash-grey weevil measuring 3-4mm long (Fig. 1; left photo). Mating and oviposition are quickly followed by eggs hatching within developing canola pods (Fig. 1; right photo). The highly concealed larvae feed within the pod, consuming the developing seeds.
Figure 1. Cabbage seedpod weevil (left) and egg dissected from within a canola pod (right). Photos: the late Dr. Lloyd Dosdall.
Damage: Adult feeding damage to buds is more evident in dry years when canola is unable to compensate for bud loss. Adults mate following a pollen meal then the female will deposit a single egg through the wall of a developing pod or adjacent to a developing seed within the pod (Fig. 1; right photo). Eggs are oval and an opaque white, each measuring ~1mm long. Typically, a single egg is laid per pod although, when CSPW densities are high, two or more eggs may be laid per pod.
There are four larval instar stages of the CSPW and each stage is white and grub-like in appearance ranging up to 5-6mm in length (Fig. 2; left photo). The first instar larva feeds on the cuticle on the outside of the pod while the second instar larva bores into the pod (Fig. 2; right photo, lower pod), feeding on the developing seeds. A single larva consumes about 5 canola seeds. The mature larva chews a small, circular exit hole (Fig. 2; right photo, upper pod) from which it drops to the soil surface and pupation takes place in the soil within an earthen cell. Approximately 10 days later, the new adult emerges to feed on maturing canola pods. Later in the season, these new adults migrate to overwintering sites beyond the field.
Figure 2. Larva feeding amongst developing seeds within canola pod (left) and larval entrance hole (right photo, lower pod) compared to mature larval exit hole (right photo, uppower pod). Photos: the late Dr. Lloyd Dosdall.
Prairie-Wide Monitoring: The annual cabbage seedpod weevil survey is performed in canola at early flower stages using sweep-net collections. Review the prairie-wide historical survey maps for this insect species. Review the PPMN monitoring protocol although the provinces of Alberta, Saskatchewan, and Manitoba have specific survey protocols for their respective network cooperators. Commercial fields where comparatively higher densities of adult cabbage seedpod weevils were observed in 2024 are highlighted yellow, orange, or red in the geospatial map featured in Figure 3.Areas where historically higher densities of cabbage seedpod weevil were observed in 2024 are worth prioritizing in 2025.
Figure 3. Densities of cabbage seedpod weevil (Ceutorhynchus obstrictus) observed in sweep-net samples retrieved from commercial fields of canola (Brassica napus) grown in Manitoba, Saskatchewan, Alberta, and the British Columbia portion of the Peace River region in 2024.
In-Field Monitoring:
Begin sampling when the crop first enters the bud stage and continue through the flowering.
Sweep-net samples should be taken at ten locations within the field with ten 180° sweeps per location.
Count the number of weevils at each location. Samples should be taken in the field perimeter as well as throughout the field.
Adults will invade fields from the margins and if infestations are high in the borders, application of an insecticide to the field margins may be effective in reducing the population to levels below which economic injury will occur.
An insecticide application is recommended when three to four weevils per sweep are collected and has been shown to be the most effective when canola is in the 10 to 20% bloom stage (2-4 days after flowering starts).
Consider making insecticide applications late in the day to reduce the impact on pollinators. Whenever possible, provide advanced warning of intended insecticide applications to commercial beekeepers operating in the vicinity to help protect foraging pollinators.
High numbers of adults in the fall may indicate the potential for economic infestations the following spring.
Albertan growers can report field observations and check the live map for CSPW posted by Alberta Agriculture and Irrigation (screenshot provided below as an example; retrieved 2025Jun19 but will be updated with 2025 reports as the season progresses).
Jennifer Otani, John Gavloski, James Tansey, Carter Peru, Shelley Barkley and Amanda Jorgensen
Categories
Week 10
Prairie-wide provincial entomologists provide insect pest updates throughout the growing season. Follow the hyperlinks to access their information as the growing season progresses:
SASKATCHEWAN’SInsect pest homepage links to important information! Busy week in Saskatchewan – please stay tuned!
ALBERTA’SInsect Pest Monitoring Network webpage links to insect survey maps, live feed maps, insect trap set-up videos, and more. There is also a Major Crops Insect webpage. Remember Agri-News includes insect-related information: • July 7, 2025, issue includes a segment on “managing high numbers of cabbage seedpod weevil” and links to “keep malathion out of canola bins”. Watch the live map for updates: • Diamondback moth pheromone trap live monitoring map for AB – Cumulative counts derived from weekly data are now being generated so refer to the Live map. • Bertha armyworm pheromone trap live monitoring map for AB – Cumulative counts derived from weekly data will be generated so refer to the Live map. • Cabbage seedpod weevil live sweep-net monitoring map for AB – In-field reports are uploaded daily so refer to the Live map. • Wheat midge live sweep-net monitoring map for AB – Cumulative counts derived from weekly data will be generated so refer to the Live map.
